Discussion:
[amsat-bb] Homebrew Elk-style 14/435 mhz log periodic for sats?
Bill Dzurilla
2009-04-18 01:15:56 UTC
Permalink
Are there plans anywhere for a homebrew version of the Elk duo bander? After reading through the prior thread about the poor performance of Eggbeaters and other omnis, I'm ready to risk the wrath of my Homeowners Association and put up a small beam.

Or, anybody have an Elk for sale?

73, Bill NZ5N
Andy MacAllister
2009-04-18 01:47:40 UTC
Permalink
Bill,

You might consider building WA5VJB's answer to the Arrow. I build the 70-cm
antenna with a PVC boom and found it to be excellent.

http://www.wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf

73 de Andy W5ACM

----- Original Message -----
From: "Bill Dzurilla" <***@yahoo.com>
To: <amsat-***@amsat.org>
Sent: Friday, April 17, 2009 8:15 PM
Subject: [amsat-bb] Homebrew Elk-style 14/435 mhz log periodic for sats?
Post by Bill Dzurilla
Are there plans anywhere for a homebrew version of the Elk duo bander?
After reading through the prior thread about the poor performance of
Eggbeaters and other omnis, I'm ready to risk the wrath of my Homeowners
Association and put up a small beam.
Or, anybody have an Elk for sale?
73, Bill NZ5N
_______________________________________________
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Gordon JC Pearce MM3YEQ
2009-04-18 08:34:18 UTC
Permalink
Post by Andy MacAllister
Bill,
You might consider building WA5VJB's answer to the Arrow. I build the 70-cm
antenna with a PVC boom and found it to be excellent.
http://www.wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf
73 de Andy W5ACM
I'll go along with that. I'm about to start on my second 3/5 element
2m/70cm yagi.

Gordon
Joe
2009-04-18 01:47:53 UTC
Permalink
You'd be amazed at what you can do with an indoor yagi also..

My first 2 meter ant was a 3 ele quad on a photo tripod that sat right
next to me on the floor in the shack,

Joe WB9SBD
Post by Bill Dzurilla
Are there plans anywhere for a homebrew version of the Elk duo bander? After reading through the prior thread about the poor performance of Eggbeaters and other omnis, I'm ready to risk the wrath of my Homeowners Association and put up a small beam.
Or, anybody have an Elk for sale?
73, Bill NZ5N
_______________________________________________
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
n***@bellsouth.net
2009-04-18 02:19:52 UTC
Permalink
Bill and all,

Joe is right. F2IL gave me a 569 report on AO-7 Mode B Thursday evening - and I was hand-holding my Elk on the second floor of my house, pointing it to the northeast at a spot on a windowless wall. When we worked, AO-7 was at roughly 3.5 degrees elevation here.

I wish I had decided to try these low-angle passes months ago!

73 to all,

Tim - N3TL
Post by Joe
You'd be amazed at what you can do with an indoor yagi also..
My first 2 meter ant was a 3 ele quad on a photo tripod that sat right
next to me on the floor in the shack,
Joe WB9SBD
Are there plans anywhere for a homebrew version of the Elk duo bander? After reading through the prior thread about the poor performance of Eggbeaters and other omnis, I'm ready to risk the wrath of my Homeowners Association and put up
a small beam.
Or, anybody have an Elk for sale?
73, Bill NZ5N
_______________________________________________
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
_______________________________________________
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Bill Dzurilla
2009-04-18 02:58:06 UTC
Permalink
Tim,

Yes, your QSO with F2IL is becoming famous, congrats. I think the performance of indoor antennas must be heavily dependent on the location of the shack and the construction materials used on the house. I moved my Eggbeater and ground plane to the attic from outside and noticed a sharp drop in performance. Also tried the Arrow here inside the shack and it did not do too well. And noticed that, even outside in the yard with the Arrow, I lose the sats at low elevation, when they drop below the level of nearby roof lines. On my DXpeditions to Swan Island and Jamaica, where there was unobstructed view over the ocean, I could easily make contacts with less than 1 degree of elevation with the same HT and Arrow.

73, Bill NZ5N
Subject: Re: [amsat-bb] Re: Homebrew Elk-style 14/435 mhz log periodic for sats?
Date: Friday, April 17, 2009, 10:19 PM
Bill and all,
Joe is right. F2IL gave me a 569 report on AO-7 Mode B
Thursday evening - and I was hand-holding my Elk on the
second floor of my house, pointing it to the northeast at a
spot on a windowless wall. When we worked, AO-7 was at
roughly 3.5 degrees elevation here.
I wish I had decided to try these low-angle passes months
ago!
73 to all,
Tim - N3TL
-------------- Original message from Joe
Post by Joe
You'd be amazed at what you can do with an indoor
yagi also..
Post by Joe
My first 2 meter ant was a 3 ele quad on a photo
tripod that sat right
Post by Joe
next to me on the floor in the shack,
Joe WB9SBD
Post by Bill Dzurilla
Are there plans anywhere for a homebrew version of
the Elk duo bander? After reading through the prior thread
about the poor performance of Eggbeaters and other omnis,
I'm ready to risk the wrath of my Homeowners Association
and put up
Post by Joe
a small beam.
Post by Bill Dzurilla
Or, anybody have an Elk for sale?
73, Bill NZ5N
_______________________________________________
are those of the author.
Post by Joe
Post by Bill Dzurilla
Not an AMSAT-NA member? Join now to support the
amateur satellite program!
http://amsat.org/mailman/listinfo/amsat-bb
Post by Joe
_______________________________________________
those of the author.
Post by Joe
Not an AMSAT-NA member? Join now to support the
amateur satellite program!
http://amsat.org/mailman/listinfo/amsat-bb
n***@bellsouth.net
2009-04-18 03:52:03 UTC
Permalink
Hey Bill,

Your comments about construction, location, etc., are right one, based on my experiences here. I actually move from one side of the house to the other depending on whether passes are to my east or west.

A couple of other things affect the performance I'm getting, too. One of the most important is that my decision to continue using a handheld antenna means I have less than six feet of coax from the radio to the antenna. I'm still getting some loss, but not nearly as much as I'd get by putting antennas in the attic and running much longer feed lines to them. Another is a little trick K4DLG in Florida passed along to me a while back.

He has a log periodic for HF, and the coax runs from the antenna feedpoint along the main boom to the back of the antenna before heading down to the shack. Taking that lead, he did the same thing with the Elk he bought. Doing so mitigated any significant changes in SWR due to moving the antenna around while hand-holding it during a pass. I tried it here and have observed the same thing. For me, at this location (inside or out), 8 degrees of elevation was the best I could hope for with the Arrow I had. In all the months I used that antenna, I made only a few contacts when a given satellite was below 8 degrees here. When I started using the Elk, that "bottom line" immediately dropped to 4 degrees. And when I tried K4DLG's suggestion of running the feedline parallel to the boom, the 4 degrees dropped to 3.

And, as you point out, depending on the location and relative path of a given pass, I can work even lower and make contacts, as I have with some stations in Europe on AO-7.

All of that being said, I also still lose the satellites due to obstruction, as you have observed with your Arrow. When it comes to the FM LEO satellites, only the ISS transmits back to us using more than milliwatt power levels. I know that AO-51 is capable of 1 watt or more, but it generally is not configured to transmit at those levels. Drew or someone, please correct me if that statement is inaccurate. The published stats on AO-27 report a nominal output of 500 mW, and SO-50 is reported to operate with a nominal 250 mW output. I believe both of them also use quarter-wave vertical antennas, which are 0-gain.

Given those power levels, it doesn't take much to begin affecting reception, especially for handheld stations.
Edward Cole
2009-04-18 05:50:29 UTC
Permalink
Just to add some observations that support yours.

I started 12 years ago with a 2m yagi supported on 15-foot mast in
the yard with 45-foot forest surrounding my property. Working 2m SSB
stations 60-70 miles away was a hit and miss, sometimes event
(running 150w). I built a 40-foot tower and mounted two 10-element
yagis made from parts of a Cushcraft 20T satellite antenna and signal
came up 3 s-units. Then I put up my antennas ten feet higher and
gained another 15-dB. Of course the antennas were then above the tree line.

On the other hand, my father wanted a low impact TV antenna at his
home in Michigan, so I suggested putting it up in the rafters of his
ranch-style single story home. I had just spent a summer in bush
Alaska putting up TV translator systems with antennas mounted inside
plywood shelters (on hill tops). My dad's antenna was set up in the
rafters of the garage. It did better than I would have expected
getting a good signal on VHF and UHF from TV stations 35-50 miles
away. 19-years later the antenna is still there working. They do
have Direct-TV dish so have more choices, now.

Point is there is more than one way to make things work...if you
understand the principles and limitations. Short coax and hand-held
antennas work pretty well, but not very convenient in some
weather. Longer coax runs and permanent antenna need a preamp to
work best. Getting the antenna clear of obstructions always is
helpful, but if you are satisfied with working only at higher
elevation angles then simple low antennas still work.

A full az-el CP yagi with preamp and auto-tracking is superb. A
simple short yagi fixed at 15 to 30 degrees and rotated in azimuth
only works too. Can you guess how well my L-band uplink will work
with a 16-foot dish and 300w? He he, well only for Oscar-zero.

73, Ed - KL7UW
Post by n***@bellsouth.net
Hey Bill,
Your comments about construction, location, etc., are right one,
based on my experiences here. I actually move from one side of the
house to the other depending on whether passes are to my east or west.
A couple of other things affect the performance I'm getting, too.
One of the most important is that my decision to continue using a
handheld antenna means I have less than six feet of coax from the
radio to the antenna. I'm still getting some loss, but not nearly as
much as I'd get by putting antennas in the attic and running much
longer feed lines to them. Another is a little trick K4DLG in
Florida passed along to me a while back.
He has a log periodic for HF, and the coax runs from the antenna
feedpoint along the main boom to the back of the antenna before
heading down to the shack. Taking that lead, he did the same thing
with the Elk he bought. Doing so mitigated any significant changes
in SWR due to moving the antenna around while hand-holding it during
a pass. I tried it here and have observed the same thing. For me, at
this location (inside or out), 8 degrees of elevation was the best I
could hope for with the Arrow I had. In all the months I used that
antenna, I made only a few contacts when a given satellite was below
8 degrees here. When I started using the Elk, that "bottom line"
immediately dropped to 4 degrees. And when I tried K4DLG's
suggestion of running the feedline parallel to the boom, the 4
degrees dropped to 3.
And, as you point out, depending on the location and relative path
of a given pass, I can work even lower and make contacts, as I have
with some stations in Europe on AO-7.
All of that being said, I also still lose the satellites due to
obstruction, as you have observed with your Arrow. When it comes to
the FM LEO satellites, only the ISS transmits back to us using more
than milliwatt power levels. I know that AO-51 is capable of 1 watt
or more, but it generally is not configured to transmit at those
levels. Drew or someone, please correct me if that statement is
inaccurate. The published stats on AO-27 report a nominal output of
500 mW, and SO-50 is reported to operate with a nominal 250 mW
output. I believe both of them also use quarter-wave vertical
antennas, which are 0-gain.
Given those power levels, it doesn't take much to begin affecting
reception, especially for handheld stations.
Rafael Valdez G.
2009-04-18 04:04:57 UTC
Permalink
Defiinetely your solution for hoa is the elk as far a I understand you can have a Tv. Antenna which te elk can fairly look like....

I am a true believer of Elk' eficiency and portability...

GL 73's

XE2RV
VUCC 164 satellite


-----Original Message-----
From: ***@bellsouth.net

Date: Sat, 18 Apr 2009 03:52:03
To: <***@yahoo.com>; <***@mwt.net>
Cc: <amsat-***@amsat.org>; <***@yahoo.com>
Subject: [amsat-bb] Re: Homebrew Elk-style 14/435 mhz log periodic for sats?


Hey Bill,

Your comments about construction, location, etc., are right one, based on my experiences here. I actually move from one side of the house to the other depending on whether passes are to my east or west.

A couple of other things affect the performance I'm getting, too. One of the most important is that my decision to continue using a handheld antenna means I have less than six feet of coax from the radio to the antenna. I'm still getting some loss, but not nearly as much as I'd get by putting antennas in the attic and running much longer feed lines to them. Another is a little trick K4DLG in Florida passed along to me a while back.

He has a log periodic for HF, and the coax runs from the antenna feedpoint along the main boom to the back of the antenna before heading down to the shack. Taking that lead, he did the same thing with the Elk he bought. Doing so mitigated any significant changes in SWR due to moving the antenna around while hand-holding it during a pass. I tried it here and have observed the same thing. For me, at this location (inside or out), 8 degrees of elevation was the best I could hope for with the Arrow I had. In all the months I used that antenna, I made only a few contacts when a given satellite was below 8 degrees here. When I started using the Elk, that "bottom line" immediately dropped to 4 degrees. And when I tried K4DLG's suggestion of running the feedline parallel to the boom, the 4 degrees dropped to 3.

And, as you point out, depending on the location and relative path of a given pass, I can work even lower and make contacts, as I have with some stations in Europe on AO-7.

All of that being said, I also still lose the satellites due to obstruction, as you have observed with your Arrow. When it comes to the FM LEO satellites, only the ISS transmits back to us using more than milliwatt power levels. I know that AO-51 is capable of 1 watt or more, but it generally is not configured to transmit at those levels. Drew or someone, please correct me if that statement is inaccurate. The published stats on AO-27 report a nominal output of 500 mW, and SO-50 is reported to operate with a nominal 250 mW output. I believe both of them also use quarter-wave vertical antennas, which are 0-gain.

Given those power levels, it doesn't take much to begin affecting reception, especially for handheld stations.
Bill Dzurilla
2009-04-18 19:11:55 UTC
Permalink
I have ordered an Elk. Any set-up tips? I see they recommend using a PVC T-connector to attach the antenna to the mast. This aims the antenna parallel to the ground. How to mount it for a fixed 20 degree elevation?

Also, as this antenna has only one feedline, is there any way to mount preamps for both 70cm and 2m?

Thanks and 73, Bill NZ5N
Subject: Re: [amsat-bb] Re: Homebrew Elk-style 14/435 mhz log periodic for sats?
Date: Saturday, April 18, 2009, 12:04 AM
Defiinetely your solution for hoa is the elk as far a I
understand you can have a Tv. Antenna which te elk can
fairly look like....
I am a true believer of Elk' eficiency and
portability...
GL 73's
XE2RV
VUCC 164 satellite
-----Original Message-----
Date: Sat, 18 Apr 2009 03:52:03
Subject: [amsat-bb] Re: Homebrew Elk-style 14/435 mhz log
periodic for sats?
Hey Bill,
Your comments about construction, location, etc., are
right one, based on my experiences here. I actually move
from one side of the house to the other depending on whether
passes are to my east or west.
A couple of other things affect the performance I'm
getting, too. One of the most important is that my decision
to continue using a handheld antenna means I have less than
six feet of coax from the radio to the antenna. I'm
still getting some loss, but not nearly as much as I'd
get by putting antennas in the attic and running much longer
feed lines to them. Another is a little trick K4DLG in
Florida passed along to me a while back.
He has a log periodic for HF, and the coax runs from the
antenna feedpoint along the main boom to the back of the
antenna before heading down to the shack. Taking that lead,
he did the same thing with the Elk he bought. Doing so
mitigated any significant changes in SWR due to moving the
antenna around while hand-holding it during a pass. I tried
it here and have observed the same thing. For me, at this
location (inside or out), 8 degrees of elevation was the
best I could hope for with the Arrow I had. In all the
months I used that antenna, I made only a few contacts when
a given satellite was below 8 degrees here. When I started
using the Elk, that "bottom line" immediately
dropped to 4 degrees. And when I tried K4DLG's
suggestion of running the feedline parallel to the boom, the
4 degrees dropped to 3.
And, as you point out, depending on the location and
relative path of a given pass, I can work even lower and
make contacts, as I have with some stations in Europe on
AO-7.
All of that being said, I also still lose the satellites
due to obstruction, as you have observed with your Arrow.
When it comes to the FM LEO satellites, only the ISS
transmits back to us using more than milliwatt power levels.
I know that AO-51 is capable of 1 watt or more, but it
generally is not configured to transmit at those levels.
Drew or someone, please correct me if that statement is
inaccurate. The published stats on AO-27 report a nominal
output of 500 mW, and SO-50 is reported to operate with a
nominal 250 mW output. I believe both of them also use
quarter-wave vertical antennas, which are 0-gain.
Given those power levels, it doesn't take much to
begin affecting reception, especially for handheld stations.
n***@bellsouth.net
2009-04-18 20:15:50 UTC
Permalink
Hey Bill,

Based on my experience with it when using the Elk as a handheld antenna, I believe I'd at least try the trick of using a 90-degree connector at the feedpoint and running your coax along the boom to the back of the antenna. By the way - the hardware/PVC necessary for mast mounting comes with the antenna. For a hand-holding handle, I needed only a few feet of PVC and one T connector, about 40 cents worth of parts. You shouldn't need anything for mast-mounting.

I don't have an answer for your preamp question because, as I recall, you're using one full-duplex radio. I'm using two radios and a duplexer here, and would opt for preamps at the radios. I know that's not as effective as mast-mounting, but it would probably have to suffice. I'm sure someone else will provide some input on this.

Best of luck with it all.

73,

Tim - N3TL
I have ordered an Elk. Any set-up tips? I see they recommend using a PVC T-connector to attach the antenna to the mast. This aims the antenna parallel
to the ground. How to mount it for a fixed 20 degree elevation?
Also, as this antenna has only one feedline, is there any way to mount preamps
for both 70cm and 2m?
Thanks and 73, Bill NZ5N
From: Rafael Valdez G. > Subject: Re: [amsat-bb] Re: Homebrew Elk-style 14/435 mhz log periodic for
Date: Saturday, April 18, 2009, 12:04 AM
Defiinetely your solution for hoa is the elk as far a I
understand you can have a Tv. Antenna which te elk can
fairly look like....
I am a true believer of Elk' eficiency and
portability...
GL 73's
XE2RV
VUCC 164 satellite
-----Original Message-----
Date: Sat, 18 Apr 2009 03:52:03
To: ;
Cc: ;
Subject: [amsat-bb] Re: Homebrew Elk-style 14/435 mhz log
periodic for sats?
Hey Bill,
Your comments about construction, location, etc., are
right one, based on my experiences here. I actually move
from one side of the house to the other depending on whether
passes are to my east or west.
A couple of other things affect the performance I'm
getting, too. One of the most important is that my decision
to continue using a handheld antenna means I have less than
six feet of coax from the radio to the antenna. I'm
still getting some loss, but not nearly as much as I'd
get by putting antennas in the attic and running much longer
feed lines to them. Another is a little trick K4DLG in
Florida passed along to me a while back.
He has a log periodic for HF, and the coax runs from the
antenna feedpoint along the main boom to the back of the
antenna before heading down to the shack. Taking that lead,
he did the same thing with the Elk he bought. Doing so
mitigated any significant changes in SWR due to moving the
antenna around while hand-holding it during a pass. I tried
it here and have observed the same thing. For me, at this
location (inside or out), 8 degrees of elevation was the
best I could hope for with the Arrow I had. In all the
months I used that antenna, I made only a few contacts when
a given satellite was below 8 degrees here. When I started
using the Elk, that "bottom line" immediately
dropped to 4 degrees. And when I tried K4DLG's
suggestion of running the feedline parallel to the boom, the
4 degrees dropped to 3.
And, as you point out, depending on the location and
relative path of a given pass, I can work even lower and
make contacts, as I have with some stations in Europe on
AO-7.
All of that being said, I also still lose the satellites
due to obstruction, as you have observed with your Arrow.
When it comes to the FM LEO satellites, only the ISS
transmits back to us using more than milliwatt power levels.
I know that AO-51 is capable of 1 watt or more, but it
generally is not configured to transmit at those levels.
Drew or someone, please correct me if that statement is
inaccurate. The published stats on AO-27 report a nominal
output of 500 mW, and SO-50 is reported to operate with a
nominal 250 mW output. I believe both of them also use
quarter-wave vertical antennas, which are 0-gain.
Given those power levels, it doesn't take much to
begin affecting reception, especially for handheld stations.
Nigel Gunn G8IFF/W8IFF
2009-04-19 03:31:51 UTC
Permalink
It only has one feedline because it's only one antenna whereas the Arrow is two seperate antennas.
If you want preamps for both bands and want to use the antenna to transnit then you'll need a pair of diplexers and RF
relays to bypass the preamp on the Tx side.

, as this antenna has only one feedline, is there any way to mount preamps for both 70cm and 2m?
Oscar Diez
2009-04-18 19:36:17 UTC
Permalink
Hi Bill,

for a homemade "Elk" style log-perodic antenna covering both the 2m and 70cm
bands see this homemade antenna (with bilingual instructions in German and
English) link:

http://www.radio-foto.net/radio/lpdadual.pdf

The text above is mostly self explaining and very simple and cheap to
construct with some basic tools on hand.

This antenna is slightly larger than the Elk (15 inch longer boom length)
which results even in a higher gain then the original Elk design. Maybe this
gives some desired extra punch for eventual indoor operation.

Good luck,

Oscar DJ0MY
Bill Dzurilla
2009-04-19 14:13:10 UTC
Permalink
I have been operating the linear sats over the past week on half-duplex, using a single IC-7000 controlled by SatPC32. I've made several contacts, but it has been quite difficult. Obviously the best remedy is to get a second rig and run full duplex, but in the meantime, does anyone have any tips for successful half-duplex operation?

One tip I received from NJ1H is to announce at the start that I am running half duplex, since most stations manually adjust the uplink so that the
downlink stays constant. If the other station knows I am running half-duplex, he should adjust the downlink instead of the uplink.

Any other suggestions?

73, Bill NZ5N
Greg D.
2009-04-21 03:03:08 UTC
Permalink
Hi Bill,

One other thing is to focus on the beginning and end of the passes, versus the center. The rate of change in the Doppler shift is the worst right at the middle of the pass (time of closest approach). Similarly, low elevation passes have less shift change than higher ones, and higher orbit satellites (e.g. AO-07) have less shift change than low orbit ones (e.g. VO-52).

Another thought is to use your own RIT to compensate for the other station's change, especially on the birds with 2m uplinks. That way you can hear him clearly without changing your own uplink.

Announcing you're running HDX will help if the operator on the other end is experienced. An inexperienced operator probably has enough to worry about, without trying to understand what to do with this new challenge. I worked an HDX operator a long time ago on RS-12/13, I think, and was puzzled why he was so difficult to work. Then I got his QSL card, listing the equipment, and understood. It was odd enough that I remember the contact to this day.

Best wishes (that you find a second rig...),

Greg KO6TH
Date: Sun, 19 Apr 2009 07:13:10 -0700
Subject: [amsat-bb] Linear sat half-duplex operating tips?
I have been operating the linear sats over the past week on half-duplex, using a single IC-7000 controlled by SatPC32. I've made several contacts, but it has been quite difficult. Obviously the best remedy is to get a second rig and run full duplex, but in the meantime, does anyone have any tips for successful half-duplex operation?
One tip I received from NJ1H is to announce at the start that I am running half duplex, since most stations manually adjust the uplink so that the
downlink stays constant. If the other station knows I am running half-duplex, he should adjust the downlink instead of the uplink.
Any other suggestions?
73, Bill NZ5N
_______________________________________________
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
_________________________________________________________________
Rediscover HotmailĀ®: Get quick friend updates right in your inbox.
http://windowslive.com/RediscoverHotmail?ocid=TXT_TAGLM_WL_HM_Rediscover_Updates2_042009
Loading...